PS3 Portal has some more information on the PlayStation 3 console.
In the case of the PS3 this equates to 12.5% of the available Cores on the CPU always reserved, an additional 12.5% sometimes taken by the OS, 12.5% of the available RSX memory and 25% of XDR Cell memory. Balancing these out, one could argue that Sony has removed up to 25% of the available CPU power and 18.75% of RAM for these features as well as others that are not mentioned here or will be added in future updates to the PS3 Operation System.
